The present invention relates generally to scheduling systems for public transit vehicles. It relates in particular to a passenger information system for providing near real time prediction of arrival times of public transit vehicles at selected boarding or disembarkation points.
Often complained of problems associated with public transportation include time wasted waiting for public transit vehicles to arrive at a passenger""s particular transit stop, and uncertainty as to service and/or arrival time at transit connections or destinations. To verify this, one need only observe bus riders standing in the street at travel stops looking as far down the road as possible, attempting to see the next bus, and doing so several times in the course of waiting for even one bus. A transit vehicle line operator usually publishes a schedule indicating arrival and departure times of vehicles for the line""s routes. The transit vehicle line operator, however, is often unable to maintain the schedule, particularly at peak traffic times, for reasons such as traffic conditions, weather conditions, passenger load, and vehicle malfunction. Furthermore, no matter how well an operator is able to maintain a schedule, a passenger who uses public transit or a particular line infrequently, or a passenger from outside of the area in which the particular transit vehicle operates, is unlikely to have a schedule readily available.
A passenger waiting at a transit stop for a transit vehicle cannot know for certain when the next vehicle will arrive at the stop. If a passenger arrives at the stop only a minute or so before a scheduled arrival time, and the next vehicle does not arrive at that time, the passenger may be uncertain as to whether or not the vehicle may have arrived and departed before he or she reached the stop, or if the vehicle will ever arrive. Such uncertainty, can, of course, be reduced by arriving sufficiently early at the stop to avoid missing a vehicle. This, however, consumes time, which essentially extends the duration of what may already be a long journey, and which might be better spent by the passenger in other more enjoyable and/or more productive activities.
Public transit passengers could make use of wasted waiting time and associated passenger stress could be reduced if a public transit vehicle arrival information system were available. Such a predictor would eliminate much of the stress related to public transit use. With such a predictor, waiting time could be used for more useful purposes, such as an extended stay at the passenger""s point of origin, shopping, work, or neighborhood exploration.
For passengers using commuter buses at peak hours another point of uncertainty may be the availability of unoccupied seats or even standing room on an arriving vehicle. Even if a waiting passenger is relatively certain that a vehicle will arrive on time, the passenger may not be certain that an empty seat will be available when the vehicle arrives, or after any other waiting passengers in a line in front of the passenger have boarded. In this regard, a predictor of passenger load (passenger load includes seat load and/or standing load) could be a valuable adjunct to a predictor of arrival.
It should be noted that it may be desirable to determine seat load and available seats or seat spaces separately from standing room load and available standing space because, for example, the type of space available may affect a potential passenger""s decision whether to ride a particular transit vehicle, wait for another bus at the same stop, go to a different stop, etc.
By way of example, a bus line may operate two or more vehicle routes between a waiting passenger""s boarding point and end destination. Travel time between the boarding and destination point along the shortest route may be forty-five minutes, and along the longest route may be sixty minutes. If a passenger waiting for the next arriving shortest-route vehicle at the boarding point were aware that only standing room would be available on the shortest-route vehicle, but that a seat would be available on a longest-route vehicle, (accurately) predicted to arrive at the passenger""s stop or boarding point at a given time, for example, five minutes ahead or five minutes behind the shortest route vehicle, in most cases, the passenger would opt for a seat on the longest-route vehicle. The additional ten or twenty minutes travelling time could be easily justified by the ability to read, work, sleep or simply travel more comfortably.
In contrast to the above situation, where a passenger""s ride is relatively short or where arrival time is more important than seat availability (for example, the passenger has little time to spare to reach work or an appointment and thus cannot wait for other buses or use a longer-route bus), the prospective passenger may elect to take the earliest scheduled arriving bus, if it has either seat or standing space.
For passengers already riding on a transit vehicle, useful information would include notice of cross streets, notice of upcoming transit stops, notice of connecting transit lines, notice of local stores and business services, the time available before the connecting transit line vehicle arrives at the transfer stop, as well as its passenger load. Such passengers may also be interested in knowing the time available between service on the same route before a following vehicle will arrive at the same vehicle stop, or the time available before a vehicle arrives going in the return direction. With such information the transit rider would know if it is time efficient to get off the transit vehicle to run an errand at a neighborhood business and catch a subsequent transit vehicle.
For transit system supervision to efficiently manage distribution of vehicles in the system, it is desirable to have available information such as the location of all vehicles operating in the system, the average speed of vehicles between various points in the system and predicted passenger loads between various points in the system.
For transit vehicle operators, receiving timely operating instructions or orders from transit system supervision would be very useful in preventing the bunching of vehicles and other inefficient use of transit vehicle capacity. Examples of such instructions include: wait; you are ahead of schedule xx minutes, reduce speed as conditions permit; speed up; you are behind schedule xx minutes, speed up as conditions and speed limit permit; skip stops; transfer passengers to other vehicles; turn back; special stops; alternate routes; etc.,
In summary, while an accurate predictor of the time of arrival would be particularly useful for a user of public transit vehicles, the usefulness of such predictors would be enhanced by making the associated status information widely available to the public and transit operators in real time, and by making the information available via a wide variety of displays and other access devices. In addition, the enjoyment and usefulness would be enhanced by providing additional status information such as the availability of seats on arriving vehicles, status information related to the location of a particular transit vehicle or vehicles, and by providing non-status information such as public announcements, news briefs and advertisements.
In one aspect, the present invention is directed to a system for notifying a passenger waiting for a public transit vehicle of the arrival time of the vehicle at a public stop. The system is applicable to a wide variety of vehicles such as boats, airplanes, helicopters, automobiles, vans, buses, trolleys, trains, etc. operating along aboveground routes, or combination aboveground routes and underground routes including tunnels. The system also is applicable to vehicles which travel along tracks, as well as to those which travel along road surfaces. Typically, the vehicle travels a predetermined route and may be situated at any location along the route. The stop is one of a plurality of stops along the route.
The system comprises six major classes of devices. These classes are: Vehicle Information Units, the Central Processor, Addressable Display Units, Non-Addressable Display Units, Telephone Information Systems, and On-Line Computer Information Systems.
The vehicle information units are comprised of a global positioning system device, or xe2x80x9cGPSxe2x80x9d device, located in each vehicle. Also located in each vehicle is an appropriate Passenger Load Sensor System or xe2x80x9cPLSSxe2x80x9d for estimating vehicle passenger load.
The GPS in each vehicle is in communication with a plurality of global positioning systems satellites for determining the location of the vehicle along the vehicle""s route.
The PLSS is any system that obtains reasonably accurate measurement of vehicle passenger load. In one preferred embodiment the PLSS measures vehicle -weight from spring deflections so that the processor of the vehicle information unit or the central processor may compute vehicle occupancy there from.
Other sensors may also collect information related to other vehicle systems the transit system wishes to monitor such as fuel, engine temperature, tire pressure, fuel mileage, or brake condition through a variety of additional sensor devices. Collectively the GPS, PLSS and these additional sensor devices are xe2x80x9cthe sensorsxe2x80x9d.
The sensors, including the GPS and PLSS in each vehicle, are connected to a processor located in each for accepting the information from GPS, PLSS and other sensors. This processor is in communication with a transceiver that may be individually addressable so that the information received from the sensors can be relayed by wireless radio signal in conjunction with telephone or other available communication systems to a central processor as polled by the central processor or according to a timed schedule.
The information relayed from the vehicle information units to the central processor includes the transit vehicle identification, its assigned route identification, the coordinates of its location, its current passenger load, and any other data collected from additional sensors.
The central processor includes both a transceiver and processor capable of polling the vehicle information units and receiving all information collected by the vehicle information units throughout the Transit System from the vehicle information units wireless transmissions in response to the polling from the central processor or according to a timed schedule.
The central processor has access to electronically stored information concerning the vehicle""s route. The route information includes the route specifications or map, and the location of each of the plurality of stops along the route. The route information includes historical or experience information, obtained from calculations of transit time for similar vehicles previously operating between appropriate points on the same transit route, and passenger load patterns experienced by other vehicles on the same route. Such historical data will be organized according to time of day, date and day of the year (i.e. Weekday, Saturday, Sunday, holiday, holiday season, rainy season, dry season, etc.).
The route information also includes contemporaneous route information received from other vehicles operating on the same route at the same time as well as operating information such as schedules.
The central processor includes means for computing, from the location of the vehicle and the electronically stored information, status information, for example, in the form of transit data tables which include the predicted arrival time of each transit vehicle operating in the system, or that will be operating in the system, at each transit stop along each vehicle""s route, and the predicted passenger load of the vehicle when it arrives at that particular stop.
In one aspect, a transit data table comprises a file of electronic records formatted to include in each record the following: vehicle identification, route number, stop number, and the estimated time of arrival at a particular identified stop number together with the predicted passenger load at the identified stop (assuming the transit data table includes one record for each transit stop). Alternatively, each record contains estimated times of arrival at all of the stops along a given vehicle""s route together with the predicted passenger load at all of the vehicle""s stops (assuming the transit data table includes one record for each vehicle operating on a transit route). In addition, the records may include other useful information, such as but not limited to, special passenger notification information and optimal bus operational information. The transit data table preferably would include records for each stop for each vehicle operating on each route in the transit system.
In another aspect, the present information system uses transit data table software of a standardized format, and standardized computers and other components, thereby permitting widespread use of the system anywhere in the world.
The central processor routinely updates the transit data tables as new information is received from the vehicle information units.
The central processor routinely broadcasts the updated transit data table or tables by wired or wireless transmission, or a combination thereof, throughout the area serviced by the transit system, together with specially addressed information intended only for particular displays known to be operating in the system. The system updates the entire transit data table for a huge transit system in near real time.
The central processor also has the capability to implement special programs and formatting instructions to construct from transit data table information, operator input, tables of information messages together with variable location, time, and climate parameters for display of those messages and tables of advertising messages and location, time and climate parameters for displaying those messages, formatted displays for individual displays known to the system to have unique locations or purposes.
In one aspect, the transit data table broadcast by the central processor is received by a non-addressable display device capable of automatically receiving the transit data table or a subset of information contained therein, storing the data received in its electronic memory, and automatically updating itself every time it receives a new transmission of the transit data table. The device can appear to be of a form similar to an alphanumeric pager, and may actually be incorporated within such a device.
The display device includes the means to interrogate the transit data table stored in its memory in order to display information useful to its user. This can be as simple as scrolling through the transit data table. However, persons skilled in information systems will design useful indexing, formatting and display techniques that make this information easy to use and understand.
Such a display device may display information including the time of day when, or the number of minutes until, the next vehicle operating on a user selected transit route will arrive at a user selected transit stop and the predicted passenger load of that vehicle when it arrives at the selected stop. The device may also contain computational means to find the most efficient route between any two transit stops.
Various forms of larger non-addressable display devices can be built to display information at transit stops, and in public places. Such displays will include the capability to be programmed to display all transit data table information relevant to users of that particular transit stop or public location, together with informational or advertising messages.
In another aspect the display device may be an addressable display device. Addressable display devices are likely to be placed at frequently used transit stops, public places, and businesses. Addressable display devices will also be placed within transit vehicles in two generally separate locations for different purposes.
Addressable display devices located at transit stops may, for example, receive transmitted data from the central processor that makes the display show not only information related to time remaining before transit vehicles serving that stop arrive, but also intersperse among such information other messages of informational or advertising character. For example, the display might indicate that the next bus will arrive in twenty minutes, then automatically select an advertising message suitable to be acted upon by a person observing such a message during that person""s wait time. For example, the system could automatically advertise cold drinks at a close by convenience store on hot days when the next vehicle is 10 minutes or more away from the vehicle stop. The system could automatically switch to displaying transit system information, civic notices or institutional advertisements not anticipating immediate response when the next vehicle is two minutes or less away from the stop.
In another aspect, similar displays installed in public places, businesses and museums permit coupling and coordinating appropriate messages with the above-described information regarding arriving transit vehicles. For example, displays may be placed near exits of department stores so that shoppers will remain in the store the indicated fifteen minutes rather than at the curb waiting for an arriving vehicle, thus generating additional sales for the retailer, then shift messages to upcoming events as the vehicles arrival becomes more immanent.
In yet another aspect, addressable display devices are mounted on or in moving transit vehicles. Three different types of displays can be placed within or on the exterior of transit vehicles operating within the transit system.
Addressable display devices for passengers preferably are mounted within the vehicle located to be in easy view of passengers. Several individual displays or a display unit with several screens can be mounted within a vehicle. These displays, for example, inform passengers of upcoming cross streets, transit stops, notice of connecting transit lines, the time available before connecting transit line vehicle arrives at the stop, or how long it will hold for passengers, notice of upcoming local stores and business services, destinations, information regarding the following transit vehicle for those who would like to step off the bus in order to do business, and informational and advertising messages related or not related to the location of the transit vehicle.
For instance, the display might show xe2x80x9cNext stop Fillmore Street, northbound connecting bus route number XX arrives in 9 minutes . . . . Why not buy roses for your loved one at Romance Flowers, XXXX Fillmore Street?xe2x80x9d
A second form of display unit located within the transit vehicle would be a display unit intended to alert only the transit vehicle operator to operational instructions from transit system supervision. For example, a display could be located in or upon the dashboard of the vehicle and have a display that indicates if the driver should wait, hold for connecting vehicle, speed ahead, skip stops, transfer passengers to another vehicle, turn back, make a special stop, use an alternative route or other information that would otherwise act to optimize utilization of transit vehicle capacity of the system.
Such driver-directed information would be based, at least in part, upon information compiled in the transit data tables.
In another aspect, a third type of addressable display unit is located at various positions on the exterior of the vehicle. Such units could receive instructions to display messages such as the arrival time of the next vehicle, displayed as this vehicle pulls away, how long the vehicle will pause at its current location (so as to prevent unnecessary heart attacks to persons racing to catch the vehicle), advertising related or not related to the location of the vehicle, time of day and climate, and other informational messages.
In another aspect, all three of the foregoing vehicle displays could access one display unit, which would direct the various messages to appropriate display screens.
All non portable display devices might be solar powered in order to be economical to install and maintain. Persons skilled in the art can devise systems to protect these displays from the elements and from vandalism.
All display devices can be designed by persons skilled in the art to provide information to persons with visual handicaps or hearing handicaps.
The central processor will also communicates the Transit Data Table and updates to an automatic telephone access system, so that any person may determine vehicle arrival information as described above by telephone inquiry of the system and selection of route and stop by input to a touch tone phone as directed by the telephone system. Also, the telephone access system can determine and recommend the best transit route to an inquirer.
Finally, the central processor will communicate the Transit Data Table and updates to computer information systems such as the Internet and the World Wide Web, so that the information may be used by others.
In one specific aspect, the present invention is embodied in a system and method using global positioning system devices mounted in individual vehicles which determine the precise coordinate/location of the individual vehicles. That information is transmitted to one or more central computers, preferably via a wireless communication link, and more generally via any of the available communications wireless links or xe2x80x9chard-wiredxe2x80x9d links, including fiber optics links, radio, satellite, microwave, cellular, telephone, etc., and combinations thereof. Then, using the coordinate information and experience (information previously determined and stored in the computer memory regarding vehicle routes, speeds during various times of the day, days of the week, holidays, inclement weather, etc.), the central computer(s) generates transit data tables containing current data regarding the routes, locations, velocity/speed, arrival time at future stops and other status and operational information for all vehicles in the system, then controls the broadcast availability of that information in a manner which provides public access to the information via any or all of a number of access devices and systems. The available access means include visual displays, audiovisual displays, telephony, computers, the Internet system, etc. In addition, combinations of such devices and systems may be used. For example, a telephone may be used to access the transit data table information. Alternatively, pagers or pager-like devices may be used to display route information. In yet another of the almost endless number of possibilities, computers, including personal, portable, notebook, palm computers and personal digital assistants, may be used to access route information which is broadcast by wireless transmission and/or supplied to the telephone network and/or to the Internet system, etc., by or under the control of the central computer(s).
In another aspect, in addition to transit data table information, public interest and commercial information, such as news briefs, announcements and advertisements, are available over the system. The public broadcast nature of the system and the many types of access means which can be used permit accessing the system and this information from essentially any location. For example, notebook or palm computers coupled with radio receivers can be carried anywhere by individuals and accessed essentially anywhere, and standard telephones can be used to access the information from any telephone installation, while cellular telephones provide access from substantially anywhere within the transit district. Stationary or semi-portable access means such as displays can be located at residential, commercial and government sites, including but not limited to homes, restaurants, department stores, offices, theaters, ball parks, libraries, schools, city hall and courthouses.
As alluded to elsewhere here, displays can be located in the vehicles for making available to the passengers and drivers the various types of publicly-available information, such as the transit data table information, advertising, news and public interest announcements. Furthermore, access means such as displays can be used to provide information that is intended primarily or solely for the driver or operator of the vehicle. Such driver-specific information displays can be used to display safety and status information and instructions such as information regarding the time and distance to the next stop(s), instructions to speed up to a certain speed or slow to a certain speed, instructions to bypass the next stop or stops, to wait at a given stop, etc. The driver information displays can be, for example, a separate display or a part of the display in the driver""s compartment.
In another aspect, the system can include one or more signal buttons which are located at suitable locations, including in transit vehicles and at transit stops, and are used to signal the central processor of the need for services, for example, mechanical breakdown, medical and/or police emergency, etc, and to request a response coupled with providing the exact location of the requester. Different circuits controlled by associated buttons or switches can be used to signal a need for different types of services and/or different levels of criticality or emergency. Preferably, to prevent inadvertent or intentional false signalling by passengers or others, the signal buttons are located in an area close to and under the physical control of the transit vehicle driver or other operator, for example, in the instrument panels of the transit vehicles.
In another aspect, the present invention additionally includes an arrangement, located on the vehicle, for determining the number of unoccupied seats in the vehicle. In one example, such an arrangement is provided by a plurality of bi-modal deflection sensors or pressure sensitive switches, one thereof mounted on each seat in the vehicle. The sensors are initially in a first mode, for example an xe2x80x9coffxe2x80x9d mode, when a seat is unoccupied and are switched to a second (xe2x80x9conxe2x80x9d) mode when the deflection sensor is activated by a passenger""s weight alighting on the seat. A microprocessor polls the sensors at frequent intervals and stores a digital representation of the number of sensors in the off mode. This representation may be communicated to the central processor together with the location of the vehicle. The processor communicates the number of unoccupied seats to the display, together with the computed arrival time, whenever the status of the vehicle is updated on the display. In another example, not exclusive, the number of unoccupied seats can be estimated from the weight of the vehicle, which itself can be derived from the relative height of the vehicle measured by means such as deflection sensors which measure the height of the vehicle relative to a fixed-height position on the suspension or elsewhere.